Keeping the blogosphere posted on the goings on of the world of submarines since late 2004... and mocking and belittling general foolishness wherever it may be found. Idaho's first and foremost submarine blog. (If you don't like something on this blog, please E-mail me; don't call me at home.)

Friday, May 23, 2008

Tracing Paper Over Nav Charts -- A Lesson Re-learned

The Royal Navy this week released the results of the official inquiry into the grounding of HMS Trafalgar (S-107) while doing Perisher PCO training back in 2002. The news reports are focusing on the use of tracing paper to cover the chart of the local oparea, which apparently obscured some information that could have prevented the grounding had it been more noticeable. An excerpt from one report:

A group of officers were in the last stage of a command examination nicknamed "The Pressure Cooker", in which they control the submarine during a simulated attack.They had submerged and trainees were estimating their position from previous track and depth readings.The tracing paper was put over the chart so they could draw their course on it - but the inquiry found it had obscured vital information.This included symbols showing the strength of the current, which led them to misjudge their position.It also hid part of the contours of the sea floor, which they were using to judge when it was safe to turn.This led navigators to change course too early and head into water where the seabed was rising sharply.The inquiry criticised the skipper and senior officers for not monitoring the sub's position separately using all navigational aids. It also recommended a ban on the use of tracing paper to overlay charts.It said: "The chart became increasingly untidy and elementary mistakes were made.

To me, this wasn't really a "training aid"-induced accident; I think all boats used tracing paper over charts when you were staying in the same small area for a long time with lots of maneuvering, whether you were doing PCO Ops or not. All submariners, I'm sure, have good stories about where training aids actually contributed to real-world casualties; unfortunately, all of mine happened back aft, so I can't talk about them. If you have any that pass the NNPI test, let's hear about 'em in the comments.

25 Comments:

Anonymous said...

Tracing paper.. What a bunch of crap... JC would have still hit the mount... So would San Fran... Greenville still would have E-Blowed before she should have... Minneapolis still would have had men topside... At least USN doesn't make such silly excuses for mishaps... When nothing else, blame it on the old man and send him down the river... Hey, it's tradition...

I'm not sure how widespread the info is, but it was an American submarine officer who had the conn on the Trafalgar when this happened. (It was an exchange programme, though he completed the entire course.)

Because of the different way British submarines divide responsibilities, he was fully cleared of anything related to the accident, but it certainly left an impression on him. The damage was only inches away from the pressure hull.

If you're curious, I've got a little more information that I can share privately.

Anyone remember that grounding of USS NATHANIEL GREENE in the Irish Sea, mid-1980's?? That incident was partially attributed to chart prep using red to mark a shallow area, then being invisible to the OOD who was wearing rig for red goggles. Thankfully, those of you younger than a certain age have never seen these monstrosities. The GREENE was so badly damaged that, despite having been recently refueled, it was decommissioned. The grounding led to 'low level white' light instead of red, among other things. The CO was the only CDR I've ever met who had no personal awards, not even a Navy Achievement Medal. As I recall, he retired with none.

I was NAV on an SSN '89 to '92. Tracing paper on the nav charts was strictly forbidden. Don't remember if it was a forcewide policy, but it was an inviolable rule on my boat. Tracing paper shifts, and obscures information on the chart. If you are operating in an area and you damage the chart through overuse, then its time for a new chart. I can't speak for what SUBSCHOOL is teaching now, but it would surprise me if basic principles of navigation had changed that much.As for the Anonymous posting regarding the use of tracing paper for a bottom contour fix -- that is a movable piece of tracing paper that is temporarily positioned over the DR, then the fix is transferred to the plot itself. It is not a "chart overlay."

anonymous said...It was likely some form of a contour plot running fix. Public info on fix by depth soundings says, quote: "copy the DR course line on a transparent sheet..."

If you've forgotten this one, skipper, you must be even older than me...so God bless.

Ya, had a terrible time all those years. But never touched bottom, never bumped another ship, never hurt the pier, and - most importantly - never had anyone in my responsibility killed or seriously injured.

Brit waters are troublesome. T ROOSEVELT hit Stauntons Bank in '68 for navigating on the wrong chart - put gravel in the torpedo room. Sounds to me that in the Perisher-class event, the water was a bit skinny to be screwing around with tracing paper and bottom-contour crap. Suggest something more important than 'gee I gotta get a good grade' should be at stake before risking a bottoming. And charts are pretty cheap. Earlier this blog had a heated wrangle about the virtues of digital charts in submarines. I weighed in and voted for them. I do again. Tracing paper. Christ, I'm not sure Nelson would have used it.

I'm glad to see that we Yanks are involved in Perisher. We should have started well before our diesel boats went away.

The areas in which Perisher is conducted are intentionally hazardous (e.g., extremely high shipping density)--as they should be--to simulate wartime conditions. As a result, I would be surprised if numerous other incidents have not occurred.

I am a retired Submarine ANAV. Tracing paper was a bad idea thats why most of us evolved to the new stuff called mylar. I used mylar on everything. For those of you officers and Navigators that thought when the chart got worn out that it was just time to replace the chart, you obviously did not have much chart prep time yourself. Mylar was durable and came in various transparencies. It was also invaluable when waterspace management schemes changed for the 18th time and you could change the mylar and establish the new boundaries without the disruption of a chart shift. Submarine groundings happen for one main reason, inattention. It takes more than just the QMOW to navigate the ship. The OOD, the ANAV, the Fathometer Watch (when stationed) and other supervisory elements all share an equal portion of responsibility for vigilance.

I was a NAV OPS, XO and CO in the seventies and eighties. We also used a tracing paper cover to the chart when operating in the same area for a long period of time. Often the tracing paper was removed for event reconstruction and a new sheet placed on the chart. Having operated in the Irish Sea on the SSBN I commanded, I will agree that there are many areas where additional caution is required. I refused to do a post availability test that required flank speed because I did not want to be the first SSBN skipper to bang the ship's nose into the side of 'the Trench' if a casualty occurred during the test. We ended up doing the test in the open ocean on the way to patrol. I understand that the two perisher instructors are being courtmartialed for the grounding since they were ultimately responsible. I know that navigation is different today, but I just wonder where the ship's company Navigation team was.

Echoing the post above, I was new in command and leaving the yards at Bremerton. One of our first taskings was Sound Trials in Dabob Bay. The staff rider in charge of the trials was a non-command senior commander who cheerfully told me my first run was to be flank, submerged, towards Bolton Peninsula and the closed end of the Bay. I told him to get stuffed, recalling that ASPRO had plowed into the Peninsula under exactly the same scenario (and I think with the same guy running the Trials). We ran the flank leg later, outbound and after we'd gotten everyone comfortable with slow-speed runs and the range guys calling the turn marks more familiar with a twin-screw diesel's characteristics, it having been awhile since they'd worked with one.

The lesson is same as poster above and in Perisher: you don't get a Navy Cross for doing stupid things in peacetime - even if you get by with it.

Along time friend couldn't sleep so he got up eary. Did his walk through, checked NavPlot and relieved the OOD. He told me all of a sudden he got a scary feeling about the plot. He checked the plot realized there was a sea mount on their track. At the time they were at flank and almost test depth. He shouted out all stop, make your depth 150 feet, and he sounded the collision alarm. All of this transpired in the first 12 minutes of his watch. I wish they had a happy ending. The boat slamed into the sea mount at 400 feet speed was under 20KTS. No one was hurt. I'm not even sure of the damage to the boat.

The LT(a ring knocker) OOD who was relieved early skated on the discipline. The Mustang LT who relieved early and saved the boat from possible death war transfered to a sub tender. The CO who was asleep was relieved of his Command.

The story is the same and the end a ticket to retirement.

This CO was a rising star. The penality was harsh as it should be.The Submarine Service lost a brillant CO.

I am with retired ANAV above. A properly prepared chart is a work of art and needs to be protected. Transparent mylar is a useful tool. If any boat has something on a chart that obscures information they are missing the big picture of having a chart. I completed my NAV, XO, and command tour before ECDIS, and while intellectually I can see its advantages and all, it would scare me to depend on it at sea. It was comforting to know that the QMOW, and he was a QM, not an ET, spent hours taking that brand new chart and turning it into a beautiful navigation tool, and he knew that chart so well he could draw it.IRT TRAFALGAR, I would say they stressed the nav team, forcing them to use an EP at almost 15 kts submerged in a "channel", but were not sufficiently concerned with the accuracy of their EP, ie, actual set/drift was significantly different from what they based their nav decisions on. Turn early in a channel, surfaced or submerged, bad things happen. Not sure I am onboard with the concept of going faster so the PUC or whatever the Brits call it does not have time to grow too big and force a fix. Interesting idea.Nice point about the "Rig for Red Goggles" and GREENE. It was not just the charts, many RED warnings in control would disappear when the goggles went on. Good thing OODs did not have to actually work anything but the scope.

When I first showed up on the boat, overlays were SOP. Then, the new (MUCH better) CO showed up (2004 timeframe) and did away with overlays. As a nub when overlays were still used, I had no experience with them, but I know I appreciated having an easily readable, well prepared chart when I did finally stand OOD. And, yes- the NAV, ANAV, and Nav ET's were chronically sleep deprived from the extra chart preparation! (Then again, who wasn't?)

Tracing paper or mylar, the rpocess I'm familiar with includes all overlays being apropriately prepped and verified. Like the ANAV said, especially when you're doing Strike Group ops and havng to keep track of emergent WSM schemes, proper use of overlays will save both your charts and your sanity.

About Me

I'm Joel Kennedy -- a married, 50-something year old retired submarine officer and esophageal cancer survivor with three kids who has finally made the transition to civilian life. Politically, I'm a Radical Moderate. (If you don't like something on this blog, please E-mail me. Don't call me at home.)